(Workaround) To remove a stubborn package on Debian.

I have a Buffalo LinkStation, which I installed Debian Stretch on it.

Recently, I was trying to remove obsolete packages by using “apt-get autoremove” command after an update. Usually this process will take a couple of minutes. But this time, unfortunately there was a package (to be more specific, an old kernel) which refused to be removed by apt or dpkg. Continue reading (Workaround) To remove a stubborn package on Debian.

CentOS 7 virt-manager “authentication failed”错误及解决方法

这两天在捣鼓CentOS 7,因为之前是在Debian用KVM,于是这次照着之前的做法来一步步安装KVM,然而最后打算用virt-manager来管理的时候,发现被拒之门外了。

virt-manager error

Unable to connect to libvirt.
authentication failed: no agent is available to authenticate.

呃,真够磨人的。看着像是权限问题。尝试了下,发现root级别的qemu:///system 是出错的,不过用户级别的qemu:///session 没有问题。因为默认是以非root用户执行virt-manager的,应该是这个原因导致权限的问题。

用户级别的权限受到很多限制,要全面发挥KVM的功能还是需要root级别。不过,现在却被挡在了门外。我先是检查了各种包有没有安装,结果是该装的都装了。 Continue reading CentOS 7 virt-manager “authentication failed”错误及解决方法

Local domain suffix causing WSUS error

I have several Windows computers in my LAN, so I’m using a Windows Server as WSUS server serving Windows Updates to LAN clients. And I just flashed my router’s firmware from Tomato to OpenWRT yesterday, then I found the WSUS service broken.

“80072ee2” shows on Windows Update window, and the Windows Server Update Service remote console unable to connect to the WSUS server neither.

The 80072ee2 means there was a connectivity issue between client and server,

Continue reading Local domain suffix causing WSUS error

用iptables加强VPS防御

VPS – Virtual Private Server,也就是虚拟专用服务器。虽说是虚拟的,但是和普通服务器一样:有内存、有CPU、有HDD当然也直接接入互联网。

实话实说,网络的凶险程度一点也不比人类社会低。接入互联网的设备,无时无刻不承受着来自各方面的攻击:比如最常见的端口扫描。
Continue reading 用iptables加强VPS防御